US3088096A - Method for the automatical recognition of characters - Google Patents
Method for the automatical recognition of characters Download PDFInfo
- Publication number
- US3088096A US3088096A US728732A US72873258A US3088096A US 3088096 A US3088096 A US 3088096A US 728732 A US728732 A US 728732A US 72873258 A US72873258 A US 72873258A US 3088096 A US3088096 A US 3088096A
- Authority
- US
- United States
- Prior art keywords
- potential
- character
- characters
- potentials
- shape
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C19/00—Digital stores in which the information is moved stepwise, e.g. shift registers
- G11C19/02—Digital stores in which the information is moved stepwise, e.g. shift registers using magnetic elements
- G11C19/04—Digital stores in which the information is moved stepwise, e.g. shift registers using magnetic elements using cores with one aperture or magnetic loop
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V10/00—Arrangements for image or video recognition or understanding
- G06V10/10—Image acquisition
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V10/00—Arrangements for image or video recognition or understanding
- G06V10/20—Image preprocessing
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V10/00—Arrangements for image or video recognition or understanding
- G06V10/40—Extraction of image or video features
- G06V10/44—Local feature extraction by analysis of parts of the pattern, e.g. by detecting edges, contours, loops, corners, strokes or intersections; Connectivity analysis, e.g. of connected components
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V10/00—Arrangements for image or video recognition or understanding
- G06V10/88—Image or video recognition using optical means, e.g. reference filters, holographic masks, frequency domain filters or spatial domain filters
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V30/00—Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
- G06V30/10—Character recognition
- G06V30/14—Image acquisition
- G06V30/144—Image acquisition using a slot moved over the image; using discrete sensing elements at predetermined points; using automatic curve following means
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V30/00—Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
- G06V30/10—Character recognition
- G06V30/14—Image acquisition
- G06V30/146—Aligning or centring of the image pick-up or image-field
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V30/00—Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
- G06V30/10—Character recognition
- G06V30/18—Extraction of features or characteristics of the image
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V30/00—Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
- G06V30/10—Character recognition
- G06V30/18—Extraction of features or characteristics of the image
- G06V30/184—Extraction of features or characteristics of the image by analysing segments intersecting the pattern
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V30/00—Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
- G06V30/10—Character recognition
- G06V30/19—Recognition using electronic means
- G06V30/19007—Matching; Proximity measures
- G06V30/19013—Comparing pixel values or logical combinations thereof, or feature values having positional relevance, e.g. template matching
- G06V30/1902—Shifting or otherwise transforming the patterns to accommodate for positional errors
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V30/00—Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
- G06V30/10—Character recognition
- G06V30/20—Combination of acquisition, preprocessing or recognition functions
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V30/00—Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
- G06V30/10—Character recognition
- G06V30/22—Character recognition characterised by the type of writing
- G06V30/224—Character recognition characterised by the type of writing of printed characters having additional code marks or containing code marks
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06V30/00—Character recognition; Recognising digital ink; Document-oriented image-based pattern recognition
- G06V30/10—Character recognition
Definitions
- FIGI RESISTANCE NETWORK CHECKING TRACK U SELECTOR TRACK U 1 I l was 1 DIODES- 1: a; k EUT TRANS/LIATOR I F o
- the characters are scanned photo-electrically along certain horizontal and/or vertical lines, thus determining the black-white transitions.
- electrical characteristics for the individual characters will result, representing a definite code of the respective character.
- this encoding is entirely arbitrary and therefore, as a rule, also ditficult to survey.
- optical scanning it has also been proposed to print the characters with an electrically conductive or magnetic ink, or the like, and to carry out the scanning along predetermined lines with the aid of corresponding sensing elements.
- Another conventional scanning method consists in determining the black contents within the type field. This, however, may result under certain circumstances, in characteristics or criterions for the individual characters, which are very difiicult to distinguish.
- a third method for recognizing characters operates on the basis of the comparison of characters with standard, stored characters. Generally, however, this method requires a large amount of equipment.
- An object of the invention is a method for the automatic recognition of characters in particular of letters and figures.
- the characters to be recognized are electrically simulated in a field of potential and the then resulting field of potential is evaluated.
- the field of potential may be suitably approximated in an electrical network, which for example, consists of a network of concentrated impedances disposed in coordinate rows and columns.
- the crossing points of the impedances which may either be simple or complex, will then be acted upon by a fixed potential in accordance with the shape of the characters.
- a potential field and current flow depending upon the shape of the scanned character will appear. Therefore, the measurement of the potential difference at definite points of the network, may be utilized as a characteristic for the recognition of the characters.
- the simulation of the characters in the resistor network may be effected in that the characters are scanned in a raster-shaped manner by one or more photocells, and that to each partial surface of the raster (b one point (P of the network is assigned, and that to those points (P whose associating partial area or surface (b either exceeds or undercuts a predetermined blackening, a voltage U is impressed.
- a further embodiment of the invention consists in that the characters are divided in such shape elements that the potential conditions, which are caused by these elements, can easily be evaluated for recognizing the characters; it may then be possible to restrict the evaluation to some very distinct horizontal or vertical lines. This, in turn, brings about a simplification of the evaluating methods and evaluating circuit arrangements.
- the characters may be divided in such a way that the shape elements are unambiguously determined by the formation of the spatial derivatives of the first and second and probably even higher order of the potential values measured along the scanning lines, so that these may be assigned to the characters in a corresponding arrangement.
- the shape elements and, consequently, the numerals may then be unambiguously recognized by bringing the scanning results separately for each scanning trace for the shape element L into the relations x m-1+ x1) for the shape element R into the relations x1 x x+1 x (UM-1+ x-l.) and finally for the shape element G into the relations wherein U indicates the photocell output potential of the respective partial area of surface b U the potential appearing at point P y of the potential field, and U the potential imprinted upon the point P.
- FIG. 1 is a general layout of one embodiment of the V FIG. 4 shows the potentials at three points of the resistor arrangement immediately successive in the x-direction with the potentials for the shape elements L and R,
- FIG. 5 shows the FIGURE 2 within a raster pattern for the area quantizing of the scanning
- FIG. 6 shows a photocell amplifier/limiter arrangement serving both the scanning of the raster pattern and the digitizing of the scanning
- FIG. 7 shows a resistor arrangement with a diode input of the output-signals of the photocell arrangement according to FIG. 6,
- FIG. 8 shows a selector arrangement for checking the potential field at three points of the resistor arrangement immediately successive in the x-direction
- FIG. 9 shows five varieties of electronic gates which may be used for the selectors Dr Dr according to FIG. 8,
- FIG. 10 shows a circuit arrangement for determining the shape elements L and R according to the output-signals of selectors Dr Dr in FIG. 8;
- FIG. 11 shows a circuit arrangement for determining the shape element G according to the output-signals of the selectors Dr and D11 in FIG. 8;
- FIG. 12 shows a translator for evaluating and trans lating the output-signals S R and S from FIGS. 10 and 11 to the numerals 0 9,
- FIG. 13 shows the numerals 1 9, 0 with the current stages
- FIG. 14 shows a circuit arrangement for measuring the current flowing into a point P
- Kiipfrniiller Einfiihrung in die theoretician Elektrotechnik, chapter III/6
- Proc. IEE vol. 96, page 163, vol. 98, page 486
- Proc. IRE August 1952, page 970
- Free. IEE vol. 101, part II, page 349 et seq.
- the potential field of a plane plate (or matrix: a matrix being, insofar as we are interested here, a two or three dimensional body in which a field is capable of being developed) of uniform electric conductivity depends upon the field margins existing therein, when assuming that at infinity the potential zero exists, and at the field margins a predetermined constant potential U In this way the potential is determined at each point by the geometrical shape of the field margins.
- the measuring of the potential and of its spatial differential quotient at any point permits one to arrive at unambiguous conclusions as to the geometrical shape of the margins.
- precise derivatives are not necessarily requisite; potential changes are also indicative of the field slope and what is sought is a field gradient (which, broadly speaking, includes either of the above) that may be utilized to determine the shape of the field margins.
- FIGURE 1 is a general layout of one embodiment of the invention, as shown in FIGS. 1a through 12.
- the character to be scanned is the numeral 2, shown in the lower left-hand side of the figure.
- the photocells convert discrete black-white areas of the figure into electric energy which is amplified, limited and then passed on to coordinate points of a resistor matrix through the diodes, as shown. Since the resistor network has its periphery grounded, the potentials impressed upon the coordinate points will create a field of potentials throughout the network.
- the network is now scanned along three tracks a, m and 0.
- successive coordinate points in the matrix in the X direction are sampled to determine the potential gradient of the field. Since this gradient is quite dependent upon the concentration of potentials it may be analyzed in the shape determiner, shown in the figure, which then stores 1 of 3 possible conditions; shape opened to the left, shape opened to the right, and shape closed.
- the results stored in each of the three shape determiners corresponding to the three tracks are then led to a translator which, through a series of gate circuits, sets a potential on one of the ten wires, 1 through 0.
- FIG. la there is shown a simple approximation obtainable by means of a coordinated arrangement of resistors.
- the resistors do not necessarily need to be real, in some cases complex resistors are likely to be of advantage.
- the potential U of the field margins is in this case fed to the intersecting points P FIG. 2 shows some field margins which may be part of the numerals 0 9 to be recognized.
- the potentials which are capable of being adjusted and, consequently, measured e.g. along the checking track m, corresponding to a number of resistors of FIG. la.
- the second and third line there are respectively given the first and the second ditierential quotient.
- the margins are divided into the four shape elements W, L, R and G. These letters are assigned to the following geometrical shapes:
- FIG. 3 shows the numerals 0 9 with the three checking tracks 0, m, and u. Each checking track is assigned to one line of resistors of FIG. 1a.
- Table I shows the shape elements respectively resulting on the three checking tracks with respect to the numerals l 9 and O. From this it may be seen that the numerals can be unambiguously recognized from the shape elements. Further it will be seen that the numeral 1 can be determined by the absence of the shape elements L, R, and G (indicated in the Table I by i, R G) on all of the three checking tracks, so that the shape element W is not required for the numeral recognition, because it is not present in the other numerals. Finally it will be seen from Table I that the middle checking track 111 is only necessary for the distinguishing the two numerals O and 8.
- the shape elements may be determined from the potential field and assigned to the characters.
- FIG. 4 shows curves of the potential conditions of the shape elements L and R, resulting e.g. between the three discrete points P P and P at which the potential values U U and U exist. Thereupon the following criteria may be read.
- the middle track m corresponds to the ordinate values of eight (8); and the lower track it corresponds to the ordinate value of five all as shown on FIG. 5.
- the potential U is imprinted upon all of those points P y whose associated partial surface areas b y are indicated by hatchlines in FIG. 5.
- no potentials are imprinted by the photocell arrangements. Since, the fixed potential zero is applied to the periphery of the resistor arrangement a potential field is effected by the scanned numeral, so that upon the scanning, this figure will be simulated within the resistor arrangement. This is the first step in recognizing the numerals.
- the second step in recognizing the numerals now consists in the evaluation of the potential field, that is, an examination is carried out as to Whether the shape elements L, R, or G are within the potential field.
- FIG. 8 shows the coupling diodes Di of one line of resistors (FIG. 7), which line corresponds for example, to the checking track 0 (FIG. 3).
- Electronic circuit elements which, in FIG. 8, are symbolically represented as rotary switches Dr, are employed for determining the potential values U,, U U as well as U at three successive points along one checking track since the checking has to be effected in a cyclical fashion.
- the rotary switches are so connected with the resistor arrangement that three successive points in the x-direction may be read out or checked concurrently.
- the first contact of the rotary switch Drl is connected with the point P while in the rotary switches Dr2 and D14 the first one, and in the rotary switch Dr3 the first two contacts are dead. Since all of the four rotary switches rotate synchronously, the first comparison of voltage can only take place in the third position of the rotary switches. In this position the points P y P y are connected with the corresponding rotary switches, so that the required checking of the above conditions (l) (4) may be carried out.
- the rotary switch Dr4 is connected with the amplifier point U and it thus serves the determination of the shape element G.
- the rotary switches Dr which are symbolically shown in FIG. 8, may be electronic gating circuits, which are actuated in a time successive manner.
- Conventional examples of five such gating circuits AA, BB, CC, DD and EE are shown in FIG. 9.
- n-p-n type junction transistors may alternatively be employed, with corresponding changes in the polarities of the potential applied to the several electrodes thereof along with other changes which are well understood by those skilled in the art.
- the coincidence gates K1, K2 are of known type and require the simultaneous application of a voltage upon both inputs thereof in order to render the gate conducting. If, furthermore U U then the transistor T2 is capable of conducting, so that a second signal will be applied to the coincidence gate K1.
- This signal will then cause the opening of the gate circuit K1 and the application of an identification signal for the shape element L to the storage device 5
- the output signal of the transistor T1 is concurrently applied to the coincidence gate K2, which will be opened whenever U U and, consequently, the transistor T3 conducts.
- the identification signal appearing at the gate K2 for the shape element R will then be fed to the storage device S
- the potentials U and U need not be obtained for the middle checking track but only the potential U as well as the potential U',;, for determining the shape element G.
- FIG. 11 the circuit arrangement for obtaining the shape element G with the conditions U U and U U is shown.
- the potential delivered by a photo cell F upon scanning of a black area is amplified by the amplifier V.
- the amplified potential is applied via the limiter B and diode to the point P y of the resistor arrangement.
- the rotary switches Dr2 and Dr4 effect a checking of the potentials existing at the two terminals of the diodes.
- the potential U is applied to the base electrode of the transistor T4, to whose emitter is applied the potential U Accordingly the transistor T4 conducts whenever U U i.e. when the corresponding photocell performs the scanning of a white raster field.
- a signal will be applied to the coincidence gate K3.
- FIG. 12 of the drawings a translator is shown which, in accordance with the identification signals of the three checking tracks 0, m and u produces the output signals for the recognized numerals 0 9.
- This translator substantially consists of coincidence gates, the input leads of which, in accordance with Table I, are connected with the storage devices or the outputs thereof. Whenever the storage devices show an absence of an input signal in all three checking tracks the numeral 1 is indicated.
- Ka is an and gate which conducts or produces a signal only in the absence of signals on all 3 inputs. This is symbolically denoted in FIG. 12 by the three input arrows E, E, and 'G' at the coincidence gate Ka for the numeral 1.
- the rotary selectors Dr Dr (FIG. 8) start to run synchronously. In the first and second position no evaluation is effected because in the rotary selector Dr the first one, and in the rotary selector Dr the first two contacts are dead. In the third position, the selector Dr is connected to the point P the selector Dr to the point R and the selector Dr to the point P Thus the potential conditions of these three points may be compared with one another. As will be seen from FIG. 5 the rise of potential is approximately linear up to the point P so that no statement can yet result as to whether the shape element L or R exists.
- An arrangement may also be made whereby the points P corresponding to white partial surface areas b y are imprinted with a fixed potential.
- the latter may also be used for character recognition, since characteristic associations exist between the flow ofcurrent within the potential field and the shape elements of the characters.
- the current I flowing into a point P corresponding to a blackened partial surface area b is greater the more exposed this partial surface area projects into nonblackened partial surface area.
- characteristic current stages for the numerals O 9 may be determined which may then be used for recognizing the respective numerals. Thus, for example, it is sufficient to provide the following five current conditions:
- the term screened implies that many black fields exist in the neighbourhood.
- the numerals are provided with the current condition identification indicia.
- the blackening of the numerals will provide an approximate indication of the current densities.
- thedivision into current conditions may also be set up more finely, so that it will be rendered possible this Table II it will be seen that nearly all figures differ from each other according to the distribution of the current intensities and, thus, may be recognized.
- Only the two numerals 6 and 9 cannot be readily distinguished from one another, but they will become distinguishable e.g. when examining in what relation the point with the current condition 3 is to the center of gravity or concentration of the numeral.
- the evaluating arrangement is e.g. capable of measur ing the currents 1, flowing into the points P of classifying these into the diiierent areas of current intensity, and of counting how many times per numeral the different stages appear.
- the particular distribution thereof will then be characteristic for the respective numeral.
- This distribution is fixed with respect to distortions (twistings) and displacements of the shape.
- the fixed distribution with respect to enlargements or reductions in size of the character may be accomplished in that the condition for the current intensity I y is set up relative to the appearing maximum and minimum value. In this way a fixed distribution with respect to changes in the type of numeral will also result.
- the measurement of the current intensities I y may be carried out with the aid of conventional means.
- a corresponding example for the measurement is shown in FIG. 14.
- the limiter output U' y is connected on one side of a resistor R with the corresponding point P y of the resistor coordinate network.
- the point A is connected with the emitter of transistor T6, while point B of the resistor is connected to the base electrode of said transistor.
- the collector electrode of the transistor T6 is coupled, across the resistor R4, to a potential which. is negative with respect to potential U' Upon scanning a white partial surface area b y (FIG. 5) the same potential will exist on both sides of the resistor R3, because no current is flowing. The transistor T6, therefore, is blocked.
- the point C may be connected with a logic circuit in which the various conditions are evaluated character recognition.
- This logic circuit also serves to determine therepetition rate of the individual conditions per character.
- the logic circuits, as required to this end are sufliciently known in the art and, therefore, do not need to be particularly described herein.
- the described automatic character recognition methods are rather insensitive to type variations. Likewise it is easy to adjust to any differences in size when first determining (e.g. with the aid of special kinds of photocells) the upper or lower margin of the characters and, thereafter, adjusting the photocells to the actual scanning operation.
- a character recognition system comprising an im- 1 1 pedance plane, means for maintaining the periphery of said plane at a fixed electrical potential, means for sensing portions of the outline of a character to be recognized, means for deriving electrical potentials differing from said fixed potential from said sensing means, means for applying said potentials to separate coordinate points of said plane, respectively, whereby said plane will provide a resultant potential field, means for scanning predetermined coordinate points in a plurality of lines across said plane for detecting the potentials thereof, and means for comparing said detected potentials for deriving an output corresponding to said character.
- a character recognition system as claimed in claim 1, wherein said means for deriving electrical potentials from said sensing means comprises amplifier-limiter elements.
- said comparison means comprises a plurality of storage devices each adapted to store information regarding particular parameters of scanned characters, a separate coincidence gate element for controlling the operation of each of said storage devices, switch means intermediate said scanning means and said gate elements for controlling operation thereof, there being at least two of said switch means coupled to each of said gate elements to effect operation thereof.
- a character recognition system comprising means for electrically simulating a character shape as a predetermined potential in a potential field, means for determining spatial potential gradients in said field, and means for evaluating said gradients whereby the character is unambigously determined.
- a character recognition system comprising an impedance matrix means for electrically simulating a character shape as a first potential in said matrix, means for maintaining the periphery of said matrix at a predetermined second potential, means for determining spatial potential gradients in said matrix, and means for evaluating said gradients whereby the character is unambiguously indicated.
- a character recognition system comprising a resistor network having a first fixed potential at its periphery, means for electrically simulating a character as a fixed second potential in said network, means for determining potential gradients in said network, and means for evaluating said gradients whereby the character is unambiguously indicated.
- a character recognition system as claimed in claim 10 in which the means for evaluating said gradients includes the approximate constitution of spatial derivatives.
- a character recognition system comprising a coordinate network of resistors, means for maintaining the periphery of said network at a predetermined potential, means for impressing potentials difiering from said predetermined potential on intersecting points of the resistor network corresponding to respective partial areas of the character, means for determining the changes in potential between coordinate points in said network, means for evaluating said changes in potential, means for translating the evaluation into indicia corresponding to the character.
- a character recognition system comprising a coordinate network of resistors maintained at a first potential, transducer means adapted to scrutinize discrete areas of a character and give potentials relative to indicia on said areas, means for assigning said potentials from said discrete areas on a one to one basis to corresponding intersecting points in said network to induce a potential field in said network, means for scanning said network and said transducer potentials in a plurality of tracks and deriving potentials therefrom, means for comparing said last mentioned potentials within each track and determining a shape element therefrom, means for translating the shape elements derived at said tracks into an indication of the character.
- a character recognition system comprising a coordinate network of resistors maintained at a first potential, a plurality of transducers coupled to intersecting points in said network on a one to one basis adapted to scrutinize discrete areas of a character and give second potentials relative to indicia thereon, unidirectional current carrying means connected between each transducer and its associated intersecting point, selector means for scan- .ning transducer potentials and network points in a plurality of tracks and deriving potentials therefrom, means for comparing the derived potentials within each track and determining a shape element, means for storing said shape element, means for translating the stored shape element of all of the tracks into an indication of the character.
- a character recognition system as claimed in claim 14 in which the selector means comprises a plurality of cyclically rotating switches adapted to scan successive intersecting points on a track and successive transducer potentials associated with those points.
- a character recognition system comprising a coordinate network of resistors grounded at its periphery, a circuit coupled to each intersecting point in said network, said circuit comprising a diode, a limiter, an amplifier, and a photocell respectively serially connected, the photocells being adapted for reading discrete areas of characters whereby each discrete area corresponds to an intersecting point in said network, a plurality of tracks in said resistor network, cyclically rotating reading means for each track adapted to read successive intersecting points and successive limiters, a shape determiner comprising transistors, and gates, and storage devices coupled to each of said reading means for determining and storing a shape element, a translator comprising a plurality of and gates and coupled to all of the shape determiners for indicating the recognized character.
- a character recognition system comprising means for electrically simulating a character shape as predetermined potential in a potential field, means for measuring the current necessary to simulate said character and means for evaluating said currents whereby the character is unambiguously determined.
- a character recognition system comprising means for electrically simulating a character shape as a predetermined potential in a potential field, means for measuring the currents in said field, and means for evaluating said currents whereby the character is unambiguously determined.
- a character recognition system comprising means for electrically simulating a character as a first potential in an impedance matrix, means for keeping the periphery of said matrix at a predetermined second potential, means for measuring the currents necessary to simulate said character and means for evaluating said currents whereby the character is unambiguously determined.
- a character recognition system comprising a coordinate network of resistors, means for maintaining the periphery of said network at a predetermined potential,
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Multimedia (AREA)
- Theoretical Computer Science (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Character Input (AREA)
- Character Discrimination (AREA)
- Tests Of Electronic Circuits (AREA)
- Shift Register Type Memory (AREA)
Applications Claiming Priority (11)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE1957ST012466 DE1069917B (de) | 1957-04-17 | 1957-04-17 | Verfahren zum maschinellen Erkennen von Zeichen |
DEST12467A DE1077904B (de) | 1957-04-17 | 1957-04-17 | Verfahren zum Ausrichten bzw. Zentrieren von Zeichen |
DEST012648 | 1957-06-08 | ||
DE1957ST012777 DE1075354B (de) | 1957-04-17 | 1957-07-17 | Verfahren und Anordnung zur automatischen Erkennung von Zeichen |
DEST12800A DE1104241B (de) | 1957-04-17 | 1957-07-24 | Verfahren zur Abtastung von Zeichen u. dgl. zwecks automatischer Erkennung |
DEST13097A DE1076984B (de) | 1957-04-17 | 1957-10-26 | Verfahren und Anordnung zur automatischen Erkennung von Zeichen |
DEST13211A DE1077464B (de) | 1957-04-17 | 1957-11-27 | Verfahren und Anordnung zum automatischen Erkennen von Zeichen, insbesondere Schriftzeichen |
DEST13329A DE1087385B (de) | 1957-04-17 | 1958-01-09 | Verfahren und Anordnung zur automatischen Erkennung von Zeichen |
DEST13783A DE1198599B (de) | 1957-04-17 | 1958-05-20 | Zweidimensionales Schieberegister |
DEST13838A DE1121864B (de) | 1957-04-17 | 1958-06-06 | Verfahren und Anordnung zum maschinellen Erkennen von Zeichen |
DEST14358A DE1116936B (de) | 1957-04-17 | 1959-10-21 | Anordnung zur automatischen Erkennung von Zeichen |
Publications (1)
Publication Number | Publication Date |
---|---|
US3088096A true US3088096A (en) | 1963-04-30 |
Family
ID=27581509
Family Applications (5)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US728732A Expired - Lifetime US3088096A (en) | 1957-04-17 | 1958-04-15 | Method for the automatical recognition of characters |
US737102A Expired - Lifetime US3104368A (en) | 1957-04-17 | 1958-05-22 | Method for the automatic identification of characters, in particular printed characters |
US747689A Expired - Lifetime US3069079A (en) | 1957-04-17 | 1958-07-10 | Automatic character recognition method |
US767895A Expired - Lifetime US3066224A (en) | 1957-04-17 | 1958-10-17 | Automatic character recognition method |
US816791A Expired - Lifetime US3136976A (en) | 1957-04-17 | 1959-05-29 | Method for the automatic recognition of characters, in particular writing characters |
Family Applications After (4)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US737102A Expired - Lifetime US3104368A (en) | 1957-04-17 | 1958-05-22 | Method for the automatic identification of characters, in particular printed characters |
US747689A Expired - Lifetime US3069079A (en) | 1957-04-17 | 1958-07-10 | Automatic character recognition method |
US767895A Expired - Lifetime US3066224A (en) | 1957-04-17 | 1958-10-17 | Automatic character recognition method |
US816791A Expired - Lifetime US3136976A (en) | 1957-04-17 | 1959-05-29 | Method for the automatic recognition of characters, in particular writing characters |
Country Status (7)
Country | Link |
---|---|
US (5) | US3088096A (de) |
BE (6) | BE566888A (de) |
CH (10) | CH365566A (de) |
DE (11) | DE1069917B (de) |
FR (2) | FR1205483A (de) |
GB (9) | GB825598A (de) |
NL (8) | NL232548A (de) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3246295A (en) * | 1959-12-14 | 1966-04-12 | Arcs Ind Inc | Scanner |
US3249766A (en) * | 1963-08-23 | 1966-05-03 | Martin Marietta Corp | Shift registers employing tunnel diodes and particular gating means |
US3278900A (en) * | 1963-04-01 | 1966-10-11 | Ibm | Character recognition system employing pulse time interval measurement |
US3358155A (en) * | 1964-10-30 | 1967-12-12 | Tektronix Inc | Gating circuit having gating oscillator with internal time delay |
US3430198A (en) * | 1959-11-13 | 1969-02-25 | Siemens Ag | Method of and apparatus for automatically identifying symbols appearing in written matter |
US3859633A (en) * | 1973-06-29 | 1975-01-07 | Ibm | Minutiae recognition system |
US3964021A (en) * | 1973-07-27 | 1976-06-15 | Visionetics Limited Partnership | Preprocessing system and method for pattern enhancement |
US4327354A (en) * | 1978-11-03 | 1982-04-27 | U.S. Philips Corporation | Learning device for digital signal pattern recognition |
US4962341A (en) * | 1988-02-02 | 1990-10-09 | Schoeff John A | Low voltage non-saturating logic circuit technology |
US5027419A (en) * | 1989-03-31 | 1991-06-25 | Atomic Energy Of Canada Limited | Optical images by quadrupole convolution |
US5033103A (en) * | 1988-12-09 | 1991-07-16 | The United States Of America As Represented By The Secretary Of The Air Force | Model of the lateral inhibition, energy normalization, and noise suppression processes in the retina |
US5062000A (en) * | 1989-09-25 | 1991-10-29 | Harris John G | "Resistive fuse" analog hardware for detecting discontinuities in early vision system |
US5440079A (en) * | 1993-06-21 | 1995-08-08 | Rockwell International Corporation | Object-background discrimination using analog VLSI circuit |
Families Citing this family (59)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3214574A (en) * | 1952-07-16 | 1965-10-26 | Perkin Elmer Corp | Apparatus for counting bi-nucleate lymphocytes in blood |
NL268306A (de) * | 1957-05-17 | |||
US3184711A (en) * | 1958-08-18 | 1965-05-18 | Ibm | Recognition apparatus |
DE1268412B (de) * | 1959-06-16 | 1968-05-16 | Intelligent Machines Res Corp | Zeichenerkennungseinrichtung |
BE628507A (de) * | 1959-10-20 | |||
DE1123852B (de) * | 1960-02-18 | 1962-02-15 | Siemens Ag | Verfahren und Anordnung zur Ermittlung der Lage von Schriftzeichen |
NL265283A (de) * | 1960-05-31 | |||
DE1154157B (de) * | 1960-06-22 | 1963-09-12 | Ibm Deutschland | Speicherverfahren |
NL279805A (de) * | 1960-07-25 | |||
DE1291923B (de) * | 1960-08-22 | 1969-04-03 | Siemens Ag | Verfahren und Anordnung zum automatischen Ablesen eines zeilenfoermig angeordneten Textes |
DE1177386B (de) * | 1961-01-05 | 1964-09-03 | Telefunken Patent | Einrichtung zur Abtastung und Zwischen-speicherung von optisch abtastbaren Markie-rungen auf Aufzeichnungstraegern, insbesondere von Zielkennzeichen auf Postsendungen |
NL276982A (de) * | 1961-04-07 | |||
US3201751A (en) * | 1961-06-06 | 1965-08-17 | Control Data Corp | Optical character reading machine with a photocell mosaic examining device |
NL278637A (de) * | 1961-06-21 | 1900-01-01 | ||
NL280656A (de) * | 1961-07-06 | 1900-01-01 | ||
DE1190711B (de) * | 1961-07-27 | 1965-04-08 | Standard Elektrik Lorenz Ag | Verfahren zum Ausrichten von Schriftzeichen od. dgl. |
NL271032A (de) * | 1961-11-03 | |||
US3284772A (en) * | 1961-11-22 | 1966-11-08 | Space General Corp | Data correlation apparatus employing cathode-ray tube input and variable resistance data storage and comparison |
US3164806A (en) * | 1961-11-30 | 1965-01-05 | Control Data Corp | Continuous register reading machine |
US3267259A (en) * | 1962-01-23 | 1966-08-16 | Gen Electric | Freight car identification system |
US3197736A (en) * | 1962-05-22 | 1965-07-27 | Ibm | Pattern recognition system |
US3275985A (en) * | 1962-06-14 | 1966-09-27 | Gen Dynamics Corp | Pattern recognition systems using digital logic |
US3275986A (en) * | 1962-06-14 | 1966-09-27 | Gen Dynamics Corp | Pattern recognition systems |
NL301979A (de) * | 1962-12-17 | |||
US3260995A (en) * | 1963-01-16 | 1966-07-12 | Textron Electronics Inc | Character reading system employing sequential sensing of matrix input |
US3293604A (en) * | 1963-01-25 | 1966-12-20 | Rca Corp | Character recognition system utilizing asynchronous zoning of characters |
US3271576A (en) * | 1963-01-29 | 1966-09-06 | Western Union Telegraph Co | Photoelectric matrix network |
FR1605054A (de) * | 1963-02-27 | 1973-01-12 | ||
US3303466A (en) * | 1963-03-05 | 1967-02-07 | Control Data Corp | Character separating reading machine |
US3268864A (en) * | 1963-03-18 | 1966-08-23 | Apparatus for feature recognition of symbols | |
US3247483A (en) * | 1963-03-26 | 1966-04-19 | Ibm | Character recognition system employing a plurality of spaced serial transducers |
DE1184534B (de) * | 1963-04-11 | 1964-12-31 | Siemens Ag | Verfahren und Schaltung zur maschinellen Erkennung von Schriftzeichen |
DE1192430B (de) * | 1963-04-26 | 1965-05-06 | Siemens Ag | Verfahren und Schaltungsanordnung zur Abtastung eines Aufzeichnungstraegers |
DE1263362B (de) * | 1963-05-30 | 1968-03-14 | Kabushiki Kaisha Hitachi Seisakusho, Marunouchi, Chiyoda-Ku, Tokio (Japan) | Verfahren zum maschinellen Erkennen von Zeichen und Einrichtung zur Durchführung dieses Verfahrens |
US3446950A (en) * | 1963-12-31 | 1969-05-27 | Ibm | Adaptive categorizer |
US3303468A (en) * | 1964-03-02 | 1967-02-07 | Ncr Co | Character recognition system employing a sensing device with a photosensitive surface |
US3525981A (en) * | 1964-07-31 | 1970-08-25 | Hitachi Ltd | Method and system for detection of pattern features |
GB1127361A (en) * | 1965-01-30 | 1968-09-18 | Emi Ltd | Improvements relating to pattern recognition devices |
US3509533A (en) * | 1965-06-07 | 1970-04-28 | Recognition Equipment Inc | Digital-analog optical character recognition |
FR1483569A (de) * | 1965-06-22 | 1967-09-06 | ||
US3508031A (en) * | 1965-08-23 | 1970-04-21 | Ind Instrumentations Inc | Control system employing card having conductive inserts |
US3479642A (en) * | 1966-02-21 | 1969-11-18 | Ibm | Threshold system |
DE1623566A1 (de) * | 1966-03-11 | 1971-01-14 | Schneider Feinwerktechnik Jos | Faseroptisches Koordinatenmessgeraet |
GB1153316A (en) * | 1966-08-30 | 1969-05-29 | Agfa Gevaert Nv | Improved Magnetic Recording Material |
US3593283A (en) * | 1966-09-19 | 1971-07-13 | Hitachi Ltd | Feature-extracting system for pattern-recognition apparatus and the like |
US3613080A (en) * | 1968-11-08 | 1971-10-12 | Scan Data Corp | Character recognition system utilizing feature extraction |
GB1262080A (en) * | 1968-11-30 | 1972-02-02 | Int Computers Ltd | Improvements in or relating to character recognition apparatus |
FR1599243A (de) * | 1968-12-12 | 1970-07-15 | ||
US3651462A (en) * | 1970-07-20 | 1972-03-21 | Ibm | Single scan character registration |
US3713096A (en) * | 1971-03-31 | 1973-01-23 | Ibm | Shift register interconnection of data processing system |
JPS5121529B1 (de) * | 1971-07-23 | 1976-07-03 | ||
US3784982A (en) * | 1971-08-16 | 1974-01-08 | Isotec Inc | Electro-optical handwritten character reader |
US3777165A (en) * | 1972-03-31 | 1973-12-04 | Electronics Corp America | Sensing apparatus |
US3879707A (en) * | 1972-12-20 | 1975-04-22 | Ibm | Character recognition system for bar coded characters |
CH591726A5 (de) * | 1973-07-30 | 1977-09-30 | Nederlanden Staat | |
US3996557A (en) * | 1975-01-14 | 1976-12-07 | MI2 Corporation | Character recognition system and method |
US4308523A (en) * | 1980-02-04 | 1981-12-29 | Compuscan, Incorporated | Apparatus and method for character recognition |
WO1996005571A1 (en) * | 1994-08-11 | 1996-02-22 | International Data Matrix, Inc. | Method and apparatus for locating and extracting data from a two-dimensional code |
CN113920497B (zh) * | 2021-12-07 | 2022-04-08 | 广东电网有限责任公司东莞供电局 | 一种铭牌识别模型的训练、铭牌的识别方法及相关装置 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2616983A (en) * | 1949-01-03 | 1952-11-04 | Rca Corp | Apparatus for indicia recognition |
US2905927A (en) * | 1956-11-14 | 1959-09-22 | Stanley F Reed | Method and apparatus for recognizing words |
US2907824A (en) * | 1957-10-23 | 1959-10-06 | Bell Telephone Labor Inc | Electrographic transmitter |
US2924812A (en) * | 1956-03-19 | 1960-02-09 | Gen Electric | Automatic reading system |
US3016518A (en) * | 1955-02-14 | 1962-01-09 | Nat Res Dev | System for analysing the spatial distribution of a function |
Family Cites Families (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2421012A (en) * | 1945-12-10 | 1947-05-27 | Thornton W Chew | Homing system |
US2571164A (en) * | 1946-02-18 | 1951-10-16 | Robert H Rines | Electric system |
DE889658C (de) * | 1946-02-25 | 1953-09-14 | Ericsson Telefon Ab L M | Elektronenentladungsgeraet |
US2523328A (en) * | 1948-06-30 | 1950-09-26 | Gen Electric | Cathode-ray mapping system |
FR958691A (de) * | 1951-04-26 | 1950-03-17 | ||
US2741312A (en) * | 1951-09-18 | 1956-04-10 | Ibm | Indicia-controlled record perforating machine |
DE1069411B (de) * | 1951-12-27 | 1959-11-19 | IBM Deutschland Internationale Büro-Maschinen Gesellschaft m.b.H., Sindelfingen (Württ.) | Anordnung zum photoelektrischen Abtasten und Auswerten von Zeichen. 24. 12. 5-2. V. St. Amerika |
NL179454B (nl) * | 1952-06-28 | Jan Hendrik Gerlings | Plaatvormig kunststofelement. | |
US2723308A (en) * | 1953-03-19 | 1955-11-08 | Bell Telephone Labor Inc | Automatic transcribing system |
US2879405A (en) * | 1953-06-29 | 1959-03-24 | Rca Corp | Semi-conductor photo-electric devices |
FR1104482A (fr) * | 1954-05-10 | 1955-11-21 | Fr D Electronique Et De Cybern | Procédé de lecture photo-numérique et dispositif pour la mise en oeuvre de ce procédé |
US2948818A (en) * | 1954-05-28 | 1960-08-09 | Parametron Inst | Resonator circuits |
US2964734A (en) * | 1955-07-11 | 1960-12-13 | George P West | Method and apparatus for sensing handwriten or printed characters |
US2932006A (en) * | 1955-07-21 | 1960-04-05 | Lab For Electronics Inc | Symbol recognition system |
NL128312C (de) * | 1955-10-20 | 1900-01-01 | ||
US2995741A (en) * | 1956-03-28 | 1961-08-08 | Rca Corp | Display |
US3072886A (en) * | 1956-04-02 | 1963-01-08 | Ibm | Apparatus for analyzing intelligence manifestations |
GB819488A (en) * | 1956-05-22 | 1959-09-02 | Int Computers & Tabulators Ltd | Improvements in or relating to record sensing apparatus |
US2918653A (en) * | 1957-02-06 | 1959-12-22 | Burroughs Corp | Character recognition device |
US2927216A (en) * | 1957-12-19 | 1960-03-01 | Burroughs Corp | Photometric character recognition device |
-
0
- NL NL229663D patent/NL229663A/xx unknown
- DE DENDAT1065198D patent/DE1065198B/de active Pending
- NL NL228298D patent/NL228298A/xx unknown
- NL NL235003D patent/NL235003A/xx unknown
- NL NL229873D patent/NL229873A/xx unknown
- NL NL226945D patent/NL226945A/xx unknown
- NL NL233689D patent/NL233689A/xx unknown
- NL NL226946D patent/NL226946A/xx unknown
- NL NL232548D patent/NL232548A/xx unknown
-
1957
- 1957-04-17 DE DE1957ST012466 patent/DE1069917B/de active Pending
- 1957-04-17 DE DEST12467A patent/DE1077904B/de active Pending
- 1957-07-17 DE DE1957ST012777 patent/DE1075354B/de active Pending
- 1957-07-24 DE DEST12800A patent/DE1104241B/de active Pending
- 1957-10-26 DE DEST13097A patent/DE1076984B/de active Pending
- 1957-11-27 DE DEST13211A patent/DE1077464B/de active Pending
-
1958
- 1958-01-09 DE DEST13329A patent/DE1087385B/de active Pending
- 1958-04-11 GB GB11515/58A patent/GB825598A/en not_active Expired
- 1958-04-11 GB GB11514/58A patent/GB825597A/en not_active Expired
- 1958-04-11 CH CH5814358A patent/CH365566A/de unknown
- 1958-04-15 US US728732A patent/US3088096A/en not_active Expired - Lifetime
- 1958-04-16 FR FR1205483D patent/FR1205483A/fr not_active Expired
- 1958-04-16 CH CH5832858A patent/CH366163A/de unknown
- 1958-04-17 BE BE566888A patent/BE566888A/xx unknown
- 1958-04-17 BE BE566889A patent/BE566889A/xx unknown
- 1958-05-20 DE DEST13783A patent/DE1198599B/de active Pending
- 1958-05-22 US US737102A patent/US3104368A/en not_active Expired - Lifetime
- 1958-06-06 DE DEST13838A patent/DE1121864B/de active Pending
- 1958-06-06 GB GB18153/58A patent/GB832326A/en not_active Expired
- 1958-06-06 CH CH6028658A patent/CH363829A/de unknown
- 1958-06-06 BE BE568374A patent/BE568374A/xx unknown
- 1958-06-16 CH CH6061358A patent/CH365568A/de unknown
- 1958-07-10 US US747689A patent/US3069079A/en not_active Expired - Lifetime
- 1958-07-11 GB GB22390/58A patent/GB871162A/en not_active Expired
- 1958-07-17 BE BE569507A patent/BE569507A/xx unknown
- 1958-07-18 GB GB23115/58A patent/GB830028A/en not_active Expired
- 1958-07-24 BE BE569689A patent/BE569689A/xx unknown
- 1958-10-17 US US767895A patent/US3066224A/en not_active Expired - Lifetime
- 1958-10-22 CH CH6529458A patent/CH362871A/de unknown
- 1958-10-22 CH CH6529358A patent/CH376693A/de unknown
- 1958-10-24 GB GB34087/58A patent/GB852665A/en not_active Expired
- 1958-10-27 BE BE572408A patent/BE572408A/xx unknown
- 1958-11-21 GB GB37539/58A patent/GB858374A/en not_active Expired
- 1958-12-22 CH CH6756258A patent/CH372865A/de unknown
-
1959
- 1959-01-02 GB GB182/59A patent/GB871163A/en not_active Expired
- 1959-01-02 FR FR788156A patent/FR75045E/fr not_active Expired
- 1959-05-20 CH CH7339659A patent/CH379576A/de unknown
- 1959-05-29 US US816791A patent/US3136976A/en not_active Expired - Lifetime
- 1959-06-05 GB GB19315/59A patent/GB878931A/en not_active Expired
- 1959-06-06 CH CH7410159A patent/CH379815A/de unknown
- 1959-10-14 CH CH7942259A patent/CH368957A/de unknown
- 1959-10-21 DE DEST14358A patent/DE1116936B/de active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2616983A (en) * | 1949-01-03 | 1952-11-04 | Rca Corp | Apparatus for indicia recognition |
US3016518A (en) * | 1955-02-14 | 1962-01-09 | Nat Res Dev | System for analysing the spatial distribution of a function |
US2924812A (en) * | 1956-03-19 | 1960-02-09 | Gen Electric | Automatic reading system |
US2905927A (en) * | 1956-11-14 | 1959-09-22 | Stanley F Reed | Method and apparatus for recognizing words |
US2907824A (en) * | 1957-10-23 | 1959-10-06 | Bell Telephone Labor Inc | Electrographic transmitter |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3430198A (en) * | 1959-11-13 | 1969-02-25 | Siemens Ag | Method of and apparatus for automatically identifying symbols appearing in written matter |
US3246295A (en) * | 1959-12-14 | 1966-04-12 | Arcs Ind Inc | Scanner |
US3278900A (en) * | 1963-04-01 | 1966-10-11 | Ibm | Character recognition system employing pulse time interval measurement |
US3249766A (en) * | 1963-08-23 | 1966-05-03 | Martin Marietta Corp | Shift registers employing tunnel diodes and particular gating means |
US3358155A (en) * | 1964-10-30 | 1967-12-12 | Tektronix Inc | Gating circuit having gating oscillator with internal time delay |
US3859633A (en) * | 1973-06-29 | 1975-01-07 | Ibm | Minutiae recognition system |
US3964021A (en) * | 1973-07-27 | 1976-06-15 | Visionetics Limited Partnership | Preprocessing system and method for pattern enhancement |
US4327354A (en) * | 1978-11-03 | 1982-04-27 | U.S. Philips Corporation | Learning device for digital signal pattern recognition |
US4962341A (en) * | 1988-02-02 | 1990-10-09 | Schoeff John A | Low voltage non-saturating logic circuit technology |
WO1992006537A1 (en) * | 1988-02-02 | 1992-04-16 | Schoeff John A | Low voltage non-saturating logic circuit technology |
US5033103A (en) * | 1988-12-09 | 1991-07-16 | The United States Of America As Represented By The Secretary Of The Air Force | Model of the lateral inhibition, energy normalization, and noise suppression processes in the retina |
US5027419A (en) * | 1989-03-31 | 1991-06-25 | Atomic Energy Of Canada Limited | Optical images by quadrupole convolution |
US5062000A (en) * | 1989-09-25 | 1991-10-29 | Harris John G | "Resistive fuse" analog hardware for detecting discontinuities in early vision system |
US5440079A (en) * | 1993-06-21 | 1995-08-08 | Rockwell International Corporation | Object-background discrimination using analog VLSI circuit |
Also Published As
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3088096A (en) | Method for the automatical recognition of characters | |
US3599151A (en) | Character recognition photosensing apparatus having a threshold comparator circuit | |
US3104372A (en) | Multilevel quantizing for character readers | |
US3705956A (en) | Graphic data tablet | |
US3182290A (en) | Character reading system with sub matrix | |
GB796579A (en) | Automatic reading system | |
GB962271A (en) | Improved system and means for high-speed identification of printed matter | |
GB827822A (en) | Character recognition equipment | |
US3457552A (en) | Adaptive self-organizing pattern recognizing system | |
US3297993A (en) | Apparatus for generating information regarding the spatial distribution of a function | |
US3634823A (en) | An optical character recognition arrangement | |
US3859633A (en) | Minutiae recognition system | |
US3319229A (en) | Signal recognition device | |
US3902160A (en) | Pattern recognition system | |
US3539994A (en) | Adaptive template pattern categorizing system | |
US3122996A (en) | heatwole | |
GB820283A (en) | Improvements in the translation of symbols into electric signals | |
US3593285A (en) | Maximum signal determining circuit | |
US3633180A (en) | Error-detecting circuit for graphic-programming matrix | |
GB850582A (en) | Improvements in and relating to electronic apparatus for reading symbols | |
US3085227A (en) | Detection of characters | |
GB896854A (en) | Improvements in legible character forms for use in combination with reading machines | |
US3496541A (en) | Apparatus for recognizing characters by scanning them to derive electrical signals | |
US3531770A (en) | Scanning and translating apparatus | |
US3303329A (en) | Mark sensing system |